There appears little elementary about Xavier Rolet’s departure from the London Stock Exchange, with one source likening it to The Hound of the BaskervillesJOHN SPRINGER COLLECTION/GETTY IMAGES

The growing row at the top of the London Stock Exchange, and the board’s refusal to spell out their stance, was likened by one source close to the controversy to a Sherlock Holmes mystery. “It’s a little bit like The Hound of the Baskervilles. It’s the dog that did not bark.”

The questions about the departure of the LSE’s chief executive, Xavier Rolet, are mounting and so too is the pressure on Donald Brydon, the chairman. Three major shareholders are demanding an explanation, with Mr Brydon increasingly seen as the assassin.

Added to that, speculation emerged yesterday that Mr Rolet would be unable to explain events directly, having signed a confidentiality agreement.